Driving mechanism for milling, boring, and like machines



Feb. 11, 1941. c. OLIVETTI 2,231,589

DRIVING MECHANISM FOR MILLING, BORING, AND LIKE MACHINES Fi-led Feb. 25, 1939 5 Sheets-Sheet l Feb. 11, 11. c. OLIVETTI 2,231,589

DRIVING MECHANISM FOR MILLING, BORING, AND LIKE MACHINES 5 Sheets-Sheet 2 Filed Feb. 25, 1939 FIG. 4

C. OLIVETTI Feb. 11, I941.

DRIVING MECHANISM FOR MILLING, BORING, AND LIKE MACHINES Filed Feb. 25, 1939 5 SheetS -Sheet 3 CamLZZo Feb. 11, 1941- c. OLIVETTI 2,231,589 DRIVING MECHANISM FOR MILLING, BORING, AND LIKE MACHINES Filed Feb. 25, 1939 5 Sheets-Sheet 4 awe/Mo e;

Feb. 11,1941.

DRIVING- MECHANISM FOR MILLING, BORING, AND LIKE MACHINES Filed Feb. 25, 1939 5 Sheets-Sheet 5 FIG-5H FIGJO CZ'mL ZZO UZZg/eZ /L c. OLIVETTI 2,231,589

Patented Feb. 11, 1941 UNITE DRIVING MECHANISM FOR MILLING, BORING, AND LIKE MACHINES Camillo Olivetti, Ivrea, Italy Application February 25, 1939, Serial No. 258,490

In Italy December 2, 1938 I 10 Claims. (01. 90-16) The present invention relates to milling and Fig. shows the machine seen at the left of boring machines, which differ in the pro-portions the operator; of their parts, but which operate in similar way. Fig. 6 shows the construction of a part of the The invention relates more specially to devices machine comprising the cutter shaft; and mechanisms which transmit the motion from Fig. 7 is a section of the movable part as in 5 a driving shaft, driven directly by a motor or Fig. 4, but detached from the fixed part of the by pulley, gearing or other means, to another machine; operating shaft, parallel to the former and Fig. 8 is a view of a part of the mechanism bearing the tool (cutter, reamer, drill, or the transmitting the motion from the pulley to the like). Said devices are made and arranged so cutter shaft seen from the front of the machine; 10 as to obtain a machine of high efficiency, quickly Fig. 9 is a section of the same part and shows adjustable, and in which, when adjusted, the tool with dotted lines the view of that part of the bearing shaft can be steadily kept in the position mechanisms which is in the rear of the machine; wanted so as to afford a precise and eflicient Fig. 10 is a front view of the part of the mawork. Moreover, the device is cheap to manuchine acting as support for the end of the cutter l5 facture as all its parts are of simple construction shaft during operation; and easy to assemble. Fig. 11 is a side view of the same;

The invention can be applied to any type of Fig. 12 shows the detail of the pulley transmilling or boring machine, but it finds its most mitting the motion of the shaft and the mode of useful application to boring machines and planer coupling it to said, shaft; 20

type milling machines of the kind in which the Fig. 13 is a view of the same; table whereon the work piece is secured can move Fig. 14 is a view of the connection of the in one direction only (generally horizontal) on cranks for fixing the movable frame to the fixed slides fixed on the frame of the machine, whilst frame in their definite position.

the spindle bearing the tool (cutter, reamer, drill The frame I (see Figs. l-2-3-5-l0-l1) 25 or the like) is maintained with its center line with suitable guides whereon the table 2 can parallel to the plane of the table and perpendicuslide, bears the bulk of the mechanisms whereby lar to the direction of sliding of the same. Said the motion is transmitted from the driving pulspindle may be made adjustable vertically, this ley (or the motor, if the machine is directly cou- V displacement taking place without angular displed to the latter) to the shaft bearing the tool 30 placement of the spindle, so as to place it in the (cutter or the like). working position at a suitable distance from the The means for obtaining the displacements of table and then fasten it in such position. This the cutter shaft and the means'for fixing the spindle can also be displaced longitudinally along same during operation form the subject of the its center line so as to locate and then fasten present invention and are described hereinafter 35 the tool (cutter) in the proper position. in their essential parts and diagrammatically In order to clearly describe the nature of the represented in the attached figures, whilst the invention, the same is now described hereinafter, longitudinal movements of the table and the conwith reference to the accompanying drawings trol of its displacements, forming the subject of 40 representing the application to aplaner type cutanother invention, are here omitted, only the 40 ting machine, although it is not intended to limit handwheel 3 used by the operator to control the the application of the invention to the special movements of said table (Figs. l--2--5-l0--l1) type of tool machine. being shown.

In the accompanying drawings, considering The assemblage of the above mechanisms is as the front the side where the operator stays supported by a rigid frame 4 (Figs 1, 2, 3, 4, 5) 45 during the milling operation, near the driving firmly secured on the frame I, rear side. crank: This frame 4 consists of a box or casing part- Fig. 1 is a horizontal section, seen from above; ly closed in its upper part 5 and lower part 6. Fig. 2 is a front view of the machine, all the The front and rear sides are provided with front part bearing the head stock; holes l3-l4 in which two bearings 'l-B are fit- 50 Fig. 3 is a rear vertical view of the. machine; ted. In these bearings l-8 rotates the shaft 9 Fig. 4 is a section of the mechanisms for which bears the driving pulley I0. Two grooves transmitting the motion from the pulley to the II and I2 with a T cross-section are cut in the cutter shaft and retaining the same in position sides following a circular arc whereof the cenduring operation; ter is on the center line of the holes |3--l4, 55

which is also the geometric axis of shaft 9 bearing the driving pulley !9.

I5 and I6 indicate two other slots, having the same cross-section, and also having a, circular arc contour with the center in the geometric axis of shaft 9, wherein fastening bolts can pass. A movable frame I! (Figs. 123-4-57- 8-9) is located inside this fixed frame or casing 4, being rotatably supported on the extensions of the bearings 7 and 8, so that its axis of revolution coincides with the shaft 9 bearing the driving pulley H1.

The frame I! is provided with holes bearing bolts 3 with heads engaging the T grooves Hi2l5-lfi, whereby said movable frame may be fastened to the fixed frame 4 and, therefore, to the bed I of the machine. Two such holes are pierced in brackets I9, 29. It is possible thereby to displace the movable frame I! and to fasten the same on the fixed frame 4 .during rotation of the pulley i9 and shaft 9.

Referring to Figs. '789, the movable frame [7, consists of two walls 2! (front) and 22 (rear) having the form shown in the figure and connected at their ends by a tile-shaped wall 23 and a bored cylinder 25, and, in an intermediate zone, by a second bored cylinder 24.

On the walls 2| and 22, besides the two holes 26 and 21 containing the extensions of the bearings "i and 8, two other holes are drilled, bearing the two coaxial bearings 28 and 29.

The bearing might be replaced by ball-bearmgs.

The center line through the holes 28-29 is located on the plane determined by the center line of the bored cylinder 25 and the center line of the bearings 1 and 8 (coinciding with the center line of the shaft 9) or on a near plane.

On the same plane, or not very far therefrom, are the holes pierced in the brackets I9- 29, containing the bolts for fastening the movable frame H to the fixed frame 4.

Another bored cylinder 30 (Figs. l69), bearing on the front end a conical bearing 3! with flange 32, can slide inside the bored cylinder 25. The rear end 33 of said cylinder 39 is of a lesser diameter, has a screw cut on its outside surface and is provided with a bearing 34 inside. The bearings 3| and 3a bear a shaft .35 bored all its length through and to which the shaft 3! bearing the cutter 38 is fixed by means of a coned extension 36, according to a method which is common nowadays to all milling machines. 7

The cylinder 30 is provided also with a groove '39 engaging with a pin or key 49, fixed to the wall 25, so that, whilst rotary motion of said cylinder is prevented, the same is free to displace longitudinally along its center line, this being required to bring the cutter to the position wanted.

This longitudinal displacement is obtained by a screw sleeve 4| with fine pitch engaging with the screw 33 and provided with a handwheel 42 which can, be turned by the operator.

The sleeve 4| has also a circular groove on the outer surface in which engages a split ring fastened to the wall 22 by screws, said split ring allowing rotation of said sleeve and preventing longitudinal displacement thereof. On said sleeve 4| is also mounted with slight friction a graduated ring M, whereby the displacement of the cutter can be controlled.

In correspondence to the conical bearing 32 45 is provided to adjust exactly the shaft on the bearing, said ring being screwed on a thread 46 on the shaft and blocked by a screw 47 on the thread of the shaft. A disc for lessening the friction may be interposed between the collar 48 and the flange 32.

The shaft 35 is provided with said front collar as whereby a gear 69 (Figs. 1-24-5--6 7-9) is fixed thereon by screws.

A shaft 53 can rotate inside the bearings 2829, and a gear 5! is fixed thereon; the width of this gear is greater than that of the gear 49, so that when the cylinder 36 is displaced longitudinally to adjust the cutter, the teeth of the gear 49 engage always completely with those of the gear 5i. The difference between the thicknesses of the gear 49 and gear 5! represent the displacement admissible for the longitudinal adjustment of the cutter.

In certain cases the milling machine might be employed as a drilling or boring machine and this difference represents the maximum length wherewith the machine can be used for these operations.

The shaft 59 bears a gear 52 engaging with a gear 53 on a shaft 54 rotatable in a bearing 55 located in a bore in the rear-wall of the movable frame l1.

Another gear 55 is rigidly coupled with the gear 53 and carried by the same shaft 54; this gear engages with a gear 57 fixed at the end of the shaft 9 bearing the driving pulley ill. The motion is transmitted by the driving pulley I to the shaft 9 and from this, through the systern of gears 51, 56, 53, 52 on the rear side of the machine, to the shaft 59 which, through the gear drives the wheel 49, the shaft 35 and, finally, the cutter.

The gears 51, 5E, 53, 52, as well as the gears 5!, 49, can be removed from the shafts which rotate them and replaced with other ones having the same distance between the center lines, so that, by changing said gears, many speeds of the cutter shaft can be obtained from a same speed of the driving pulley.

The gears 51, 56, 53, 52 are in their assembly a set of gears as in screw cutting lathes and other tool machines and are easily interchangeable. Also gears 5i and 49 may be changed with other ones so as to have a further series of different speeds.

Casings not indicated in the drawings protect these gears and provide lubrication thereof; they also prevent longitudinal displacements of said gears, as usually performed in many of such machines.

The vertical displacement of the shaft 3'! (and therefore of the cutter) is obtained and controlled by a vertical screw 58 (Figs. 459) driven by a handwheel 59 (Figs. 234-59) The screw 58 can turn, on apposite smooth portions thereof, in two holes pierced in the walls 5 and 9 of the fixed frame or casing i and is guided so as to prevent vertical displacements.

The screw 53 engages with a nut 68 enclosed within two flanges 9i having vertical parallel flanges projecting from the movable frame H.

The nut as is provided with lateral upper and lower expansions whereby it encloses the flanges 6i so as to trail the same when displacing.

A certain clearance is left between expansions and flanges, so as to allow the slight displacement which is necessary because the nut moves along a rectilinear path whilst the flanges move along a circumference.

Owing to the devices described above, when the vertical adjustment has been obtained, by tightening the bolts fastening the fixed fame 4 on the movable frame I! .as shown above, all the mechanism supported by the latter and consequently also the cutter shaft are fixed in the desired position. A graduation on the lower part of the handwheel 59 may facilitate said adjustment.

In the internal hole of the cylindric connection 24 already described may be located and fixed a strong bar 62, as lon at least as the width of the machine, serving to connect the movable frame I! with another movable piece 63 bearing a bushing or stock head 64; inside which the end of the shaft 3'! bearing the cutter can rotate. The means for fixing the bar 82 to the movable frame I 1 may be similar to those used in known milling machines, but the means for supporting the part 63, and bushing 64, and for fixing the same to the bed i, form part of the invention and are therefore particularly described.

A sort of hollow frame 65, having the shape represented in vertical projection by Fig. 1 and .also by Figs. 510l 1, is fixed on the front part of the machine bed. This frame 65 is provided at its lower part with a base 66 which by means of bolts 61 ban be secured over two T grooves 68 parallel to the center line of the cutter shaft and cut out in the bed of the machine so that the frame 55 can be displaced more or less according to the width of the piece to be milled, and can be worked under the best conditions.

For displacing the frame 65 parallel to itself, this is guided by a block 69 whereof the sides are parallel to the center line of the cutter and which is fixed to the bed of the machine.

A groove cut in the foot 66 of the frame 65 engages exactly with slight friction on said block 69, so that the frame 65 is perfectly guided Without rotation during its displacement. Said displacement of the vertical frame 65 may be facilitated by providing the bottom of the latter with a rack engaging with a pinion whereof the axis must be perpendicular to the displacement,

. or else by means of a quadrilateral link with axes perpendicular to the direction of the displacement, or by other known mechanical means.

When the desired displacement of the frame 65 is obtained, this is fixed to the machine bed by means of bolts 61. In the frame 65 is pierced a hole whereof the center line coincides with that of the shaft 9 bearing the pulley l0.

Inside this hole is located, and can be fastened, a cylindric piece l0 ending with a screwed part of lesser diameter. The frame 65 at the opposite end is provided with a T groove having the profile of a circular arc with the center on the center line of the cylindric piece 10 and, therefore, also on the prolonged center line of shaft 9.

A piece 63, having the shape as in the drawings, rests on the vertical side of frame 65. Said piece has four holes one of which fits to the surface of the piece 10, another on the center line of the shaft 31 bearing the cutter fits to the bushing 64 whereon said shaft rotates, another is pierced on the center line of groove H and the fourth is on the center line of the bar 62 passing therethrough and fittin thereto. While the movable frame ll, by means of the screw 58, is brought to the desired position then fastened to the fixed frame 4 as described above, the piece 63 can rotate with slight friction on the outer surface of the cylindric piece 10. During this rotation, the piece 63 is trailed by the bar 62 and, consequently, the bearing 64 is also trailed and the cutter shaft 31 can continue its rotation inside the same, owing to the above coincidence of the rotational axes of the system and the cutter shaft.

When the movable frame H has been fastened to the fixed frame 4 in the position wanted, the piece 63 can in turn be fixed and pressed against the outer surface of the vertical frame 65 by means of a bolt 12 entering in the T groove H and a tapped nut or crank 12 engaging with the worm of the piece 10.

The bar 62 can be fastened also on the piece 63 by a locking split ring with a screw or screw crank in a normal manner. By the above devices the piece 63 and, consequently the bushing 64, follow the movements of the movable frame exactly and can be easily adjusted in the position required.

The bushing 64 may also be replaced by a screw journal ending with a conical point engaging with a conical cavity drilled at the end of the shaft 31, this system bein preferable, however, only for light work.

Bushing similar to the bushing 64 may be interposed and supported by the bar 62. The bar 62 has in the figure a cylindric shape as this is of easier construction and adjustment, but may have also other shapes, such as that of a piece with a reverse U cross section, the subject of this invention consisting in the function of this piece and not in its shape.

The main features of this invention concern: the form of thefixed frame 4; the form of the movable frame ll; the assembly of the mechanisms transmitting the motion from the driving pulley to the cutter shaft; the means for displacing said mechanisms and fixing the movable part to the fixed frame and consequently to the machine bed; the form of the piece bearing the bushing supporting the end of the cutter shaft; the means for displacing and successively fixing said piece to its vertical support, so as to form a rigid whole with the machine bed.

Figs. 12 and 13 show a cross section and a front view of shaft 9 and driving pulley ill and the device for transmitting the motion from the pulley to the shaft 9 and from the latter to the set of gears driving the cutter shaft. A collar 14 is slidable on the shaft 9 which is provided with a key 15 to prevent the rotation of said collar, allowing, however, the longitudinal displacement.

The collar 14 is provided with teeth 16, which, by the longitudinal displacement of the collar can engage with other teeth on a bored piece Tl ending with a circular flange 18.

The flange 18 is fixed on the pulley ill as fol lows: said flange is provided with three slots along a circumference with the center on its center line of the shaft. The slots have a certain angular amplitude and engage with three bolts 80 screwed on the pulley and having a thickened middle section, of a diameter equal to the width of the slot, minus a slight clearance which will be hereinafter explained. The length of the cylindric middle section of the bolts is slightly greater than the thickness of the flange 18, so that, putting a ring 8| on the bolts locking the nuts 82, the flange I3 is pressed with slight friction and can rotate, relatively to the pulley l0, through an angle limited by the peripheral lengths of the-slots 19.

The piece 11 of the toothed part has the same diameter of the hub 83 of the pulley H1 and can rotate thereon.

A strong spring 84 is enclosed within the space with cylindric walls existing between the piece TI and the hub 83, said spring being fixed at one end'to the inner wall of the pulley l and at the other to the piece 11. This spring 84 is initially tensioned, and, therefore, the three bolts 80 are pressed, in correspondence to their cylindric middle section, against the ends of the three slots and, when the machine is at rest, and the collar clutch is not inserted, the piece TI is unitary with the pulley. When theclutch is inserted and the machine is started, owing to the inertia of the shaft 9 and the whole device actuating the cutter and, mainly, to the resistance met by the Work to the cutter, the spring becomes further tensioned-and a slight rotation takes place between, the pulley and the flange 18 and, therefore, the rest of the mechanism, said rotation damping the starting action and being limited by the amplitude of the circular slots 79. By this way the operation of the machine is rendered gentle and uniform by the action of the spring 84 and the mechanisms are preserved against sudden jerks.

This result is enhanced by the fact that the cylindric section of the bolts 8i), located in the cavity between the circular slots T9 is slightly lesser than the width of said slots, as specified above.

The inner walls of the pulley iii and ring 8| prevent the air existing inside the slots 79 from escaping through other ways, so that there is a certain damping influence due to the air forced between the walls of the slots 79 and that of the cylindric middle section of the three bolts 80.

The same elastic system may be adopted also in the case of drive by gear instead of pulley.

The pulley ID is provided with a lateral sprocket 85, the teeth of which can engage with a chain of the Galle or other type.

By means of this sprocket and a chain not shown, the motion of the driving pulley H] can be transmitted to another part of the machine, to the mechanism of translation of the table 2, to the oilpump and other devices of the machine, this part, however, not being described as not forming part of the invention.

The nuts of the bolts l8 which fix the movable frame IT to the fixed frame may be replaced by more easily manipulated screw threaded handles. In Fig. 4, 8'! designates the handle replacing the nut of bolt in groove H and in Fig. 14, 86 designates fixing the handle replacing the nut of bolt in groove 25. To facilitate the fixing operations the handles 8% and 81 may be interconnected so that, by moving two handles only on one side of the machine, the movable frame ll can be firmly fastened to the fixed frame 4 and, therefore, to the rest of the machine. A diagram of said connection is illustrated by Fig. 14, where 87 indicates the locking handle, 35 is the right handle; 83 is a rod for transmitting rotation through a certain angle from the position indicated by the full line to the one indicated by the dotted line.

It is to be noted that the relative position of the two handles is such that the locking of the two bolts takes place successively, owing to one handle being at a dead center with respect to the connecting rod whilst the other handle is locked. In this way the locking strain is exerted alternatively. on one handle only. The nuts, however. must be threaded in opposite directions.

The movable frame I! has been described as entirely placed inside the fixed frame 4. The same result would be obtained, however also if a part of the movable frame is .outside the fixed fixing the movable frame IT to the fixed frame 4, this facilitating the assembly. These construc tional details, like others, are not represented in the drawingsas they are well known.

What I claim is:

1. In a machine tool, driving mechanism com- 10 prising a drive shaft, a tool shaft parallel to the drive shaft. intermediate shafts parallel to the drive shaft and movable in a circular path around the same, gear means between intermediate shafts and said drive and tool shafts, a frame pivotable 1 about the axis of the drive shaft, supporting means for the shafts of said set fixed in said frame, a casing fixed on the bed of the machine tool and having walls surrounding the pivotable frame, and means for connecting said walls to the said frame whereby these parts form a rigid assembly holding said tool shaft in desired position in said circular path.

2. Mechanism according to claim 1, wherein the pivo-talble frame is connected to the casing by means of T grooves cut in the casing and located near the tool shaft and other similar grooves located near the driving shaft, bolts being provided applied on the said frame and engaging by their heads in said grooves.

3. Mechanism according to claim 1 wherein the pivotable frame and fixed casing comprise two sides parallel to each other and connected to each other by connecting members one of which consist of a bored cylinder coaxial with the tool 3 shaft and provided with a seat for a nut actu' ated by a screw, in such a manner that displacement of said nut rotates the said frame to bring the tool shaft to the position required, said frame being provided with bolts for fastening the same on the fixed casing and a bar for the connection with another part of the machine carrying the bearing of the tool shaft.

4. Driving mechanism for machine tools according to claim 1 in which the gear means comprise pairs of gears mounted on the various shafts, whereof the first pairs, starting from the driving shaft, are located on the rear part of the machine in an easily accessible position to facilitate change of gears, whilst the last pair is located on the front part of the machine, the driven gear being preferably connected with the tool shaft.

5. Driving mechanism for machine tools, accord-ing to claim 1 in which the gear means comprise pairs of gears mounted on the various shafts, whereof the first pairs, starting from the driving shaft, are located on the rear part of the machine to an easily accessible position to facilitate change of gears, whilst the last pair is located on the front part of the machine, the driven gear being preferably connected with the tool shaft, and in which the gear transmitting the motion to the tool shaft is mounted as near as possible to said tool.

6. Mechanism according to claim 1 comprising a man'dril non-rotatably axially displaceable in the pivotable frame and, provided with a handwheel, a shaft actuated by said mandril, bushings supporting said shaft for rotation but not longitudinal displacement relatively to said mandril,

and means connecting said shaft with the tool shaft.

7. Mechanism according to claim 1 comprising a'vertical screw rotating in bushings fixed on the machine bed, a handwheel fixed on said screw, a. nut engaged by said screw and carried by the pivot frame so that it cannot rotate in but transmits its movements to the latter, said nut being capable of slight displacement with respect to the frame to provide for the difference between the paths of the nut and the frame.

8. A driving mechanism for machine tools com prising a driving shaft and a set of shafts, including a tool shaft, parallel to the driving shaft, a frame supporting said set of shafts whereby they are a frame supporting said set of shafts whereby they are circularly displaceable around the driving shaft and fixable in any position desired, means sup-porting the tool shaft at its rear end, a connecting member carrying said supporting means and rotatable through a certain angle about an axis which coincides with the extended axis of the driving shaft, a vertical frame member on the machine tool bed, means including nut and bolt members in said connecting member said means engaging in a circular groove of T section out in said vertical frame member and having its center in the axis of the driving shaft, a longitudinal bar sustaining said connecting member and supported by said movable frame said bar beingfixable onand displaceable with said frame through a certain angle, a bushing 9. Mechanism according to claim 8 wherein the frame member with the vertical wall whereto' the movable part carrying the bushing support- 1 ing the end of the tool shaft can be fixed, is displaceable parallel to itself in the direction of the axis of the driving shaft, and means are provided for guiding said frame and locking it in the position desired.

.10. In a machine tool, driving mechanism comprising a drive shaft, means supporting said shaft, a set of shafts parallel to the drive shaft and movable in a circular path around the same, one of said shafts having means for carrying a tool, a frame rotatably mounted on the support means of the drive shaft, supports for the circularly movable shafts, said supports being fixed in said frame, a casing enclosing the rotatable frame and fixed to the bed of the machine tool, said casing having a T groove therein, and locking bolts for said frame having heads engaging the T groove whereby the tool shaft can be fixed in desired position in said circular path, two of said bolts being in proximity of the supports of the tool shaft.

CAMILLO- OLIVETTI. 

